An investigation to evaluate impacts of the release of dredged material on chemical and physical aspects of the aquatic and benthic environments as well as phytoplankton, zooplankton, benthos, and fish was conducted in Lake Erie off Ashtabula, Ohio, from June 1975 through September 1976. Samples and measurements were taken prior to, during, and after the release of materials from a hopper dredge during August 1975 and May 1976. The impacts on the water column including the phytoplankton and zooplankton communities were short-lived. While the benthos as well as the chemical and physical nature of the sediments were altered, predisposal conditions generally were reestablished within a year after the release of the dredged material. Storm event related erosion of the dredged material appeared to be a major factor in the recovery of the area. There was no evidence of accelerated uptake of heavy metals by fish or benthos as a consequence of disposal. Harbor macroinvertebrates, transported with the dredged materials, did become established in the deposition area.